1. Field of the Invention
The present invention relates generally to nuclear detection, and, more particularly, to a portable gamma radiation detector.
2. Background Description
Radioactive nuclear materials can be used to contaminate water supplies, business centers, government facilities, or transportation networks. They can cause physical disruption, interruption of economic activity, post-incident cleanup, and psychological trauma to a workforce and populace. In fact, the possibility of a radiological terrorist attack, often referred to as a “dirty bomb,” is a fear that drives many anti-terrorism preparedness efforts. Accordingly, detection of nuclear materials prior to their use is desirable.
Several techniques exist for the detection, classification, and analysis of the spectra of nuclear materials. These include sodium-iodine detectors, high-purity germanium detectors, ionization chambers, energy-insensitive neutron detectors, and mass spectrographs. These techniques all use the same method of spectral analysis for the purpose of identifying and classifying nuclear radiation. This method is not immune to noise or clutter, thereby providing unsatisfactory output.
Mechanically, existing radioactive material detectors are large in size and extremely fragile, making them unsuitable for remote sensing and detecting applications, for example within the mass transit system of a major metropolitan area. Furthermore, extant systems require a long acquisition time for isotope identification and classification, and do not provide spatial directivity. This is undesirable from a rapid response or rapid reaction standpoint.